萝卜和裂果萝卜不开裂果实的果皮生物力学与萌发生理学比较

Comparative pericarp biomechanics and germination physiology of Raphanus raphanistrum and Raphanus pugioniformis indehiscent fruits.

作者信息

Steinbrecher Tina, Bhattacharya Samik, Binder Jonathan, Kleemeier Katharina, Przesdzink Felix, Groene Franziska, Jacoblinnert Kyra, Mummenhoff Klaus, Leubner-Metzger Gerhard

机构信息

Seed Biology and Technology Group, Department of Biological Sciences, Royal Holloway University of London, TW20 0EX, Egham, UK.

Department of Biology, Botany, University of Osnabrück, D-49076 Osnabrück, Germany.

出版信息

Ann Bot. 2025 May 9;135(5):977-990. doi: 10.1093/aob/mcaf015.

DOI:10.1093/aob/mcaf015

PMID:39868575

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC12064425/

Abstract

BACKGROUND

The biomechanical, morphological and ecophysiological properties of plant seed/fruit structures are adaptations that support survival in unpredictable environments. High phenotypic variability of noxious and invasive weed species such as Raphanus raphanistrum (wild radish) allow diversification into new environmental niches. Dry indehiscent fruits (thick and lignified pericarp [fruit coat] enclosing seeds) have evolved many times independently.

METHODS

A multiscale biomechanics and imaging (microscopy, X-ray, finite element stress simulation, puncture force analysis) approach was used to comparatively investigate the indehiscent fruits of R. raphanistrum (global weed), R. pugioniformis (endemic weed) and R. sativus (cultivated radish).

RESULTS

The hard pericarp of Raphanus species (Brassicaceae) imposes mechanical dormancy by preventing full phase-II water uptake of the enclosed seeds. The apparently unilocular fruits of Raphanus species develop from two fused valves, pericarp rupture to permit germination is confined to the midvalve regions, and each midvalve region contains a predetermined breaking zone that is biomechanically defined by the internal shape of the seed chambers. Direct biomechanical analysis revealed great variability in within-fruit and between-fruits pericarp resistances.

CONCLUSIONS

Variability in pericarp-imposed dormancy provides a bet-hedging strategy to affect soil seed bank persistence and prolong the germinability period.

摘要

背景

植物种子/果实结构的生物力学、形态学和生态生理学特性是支持在不可预测环境中生存的适应性特征。诸如野萝卜（Raphanus raphanistrum）等有害和入侵杂草物种的高表型变异性使其能够多样化进入新的生态位。干燥不裂果（包裹种子的厚且木质化的果皮[果壳]）已经多次独立进化。

方法

采用多尺度生物力学和成像（显微镜、X射线、有限元应力模拟、穿刺力分析）方法，对全球杂草野萝卜、地方性杂草裂叶萝卜和栽培萝卜的不裂果进行比较研究。

结果

萝卜属（十字花科）物种的硬果皮通过阻止内部种子的完全II期水分吸收来施加机械休眠。萝卜属物种看似单室的果实由两个融合的心皮发育而来，果皮破裂以允许萌发仅限于心皮中部区域，并且每个心皮中部区域包含一个由种子腔内部形状在生物力学上定义的预定断裂区。直接生物力学分析表明，果实内部和果实之间的果皮抗性存在很大差异。